Verticillium dahliae, a notorious phytopathogenic fungus, is responsible for vascular wilt diseases in numerous crops. Uncovering the molecular mechanisms underlying pathogenicity is crucial for controlling V. dahliae. Herein, we characterized a putative oxidoreductase-like protein (VdOrlp) from V. dahliae that contains a functional signal peptide. While the expression of VdOrlp was low in artificial media, it significantly increased during host infection. Deletion of VdOrlp had minimal effects on the growth and development of V. dahliae but severely impaired its pathogenicity. Metabolomic analysis revealed significant changes in organic heterocyclic compounds and phenylpropane compounds in cotton plants infected with ΔVdOrlp and V991. Furthermore, VdOrlp expression was induced by lignin, and its deletion affected the metabolism of host lignin and phenolic acids. In conclusion, our results demonstrated that VdOrlp plays an important role in the metabolism of plant phenylpropyl lignin and organic heterocyclic compounds and is required for fungal pathogenicity in V. dahliae.
Keywords: VdOrlp; Verticillium dahliae; lignin; organoheterocyclic compounds; pathogenicity; phenylpropanoids.